Under agreed planning rules, the site is not allowed to transport coal from the site via road. All extract is therefore moved to the rear (East) of the site where the coal is separated and washed at the Cwmbargoed Washery. Built in 1959 on land to the north and east of the railway connection to Fochriw Colliery, the coal washery was refurbished by Celtic Energy in 1992. DB Schenker trains then move the washed coal from site to Aberthaw Power Station, along the former route of the Rhymney Railway.[7] Joining the modern Rhymney Line just south of Ystrad Mynach railway station, the trains then travel onwards via Cardiff and the Vale of Glamorgan Line to Aberthaw, enabling Ffos-y-fran to supply 40% of the coal to Aberthaw power station.

The Latin language and some Roman customs and culture became established before the withdrawal of the Roman army. The Christian religion was introduced throughout much of Wales by the Romans, but locally, it may have been introduced later by monks from Ireland and France who made their way into the region following rivers and valleys.